Development and validation of a nomogram for the prediction of lymph node metastasis within 2‐year postoperatively in cT1‐T2N0 oral squamous cell carcinoma

BACKGROUND: The current neck management for early oral squamous cell carcinoma (OSCC) has always been a controversial issue. A comprehensive model is necessary for predicting an individual's metastasis risk and appropriate patient counseling. METHODS: A nomogram for predicting 2-year LNM in patients with cT1-2N0 OSCC was developed and validated using clinicopathological data from 642 patients from 2000 to 2018 in four hospitals, China. RESULTS: Three variables (pathology grade, depth of invasion, tumor-infiltrating lymphocytes) were included in nomogram. C-indices were 0.826 (95% CI: 0.786-0.866) and 0.726 (95% CI: 0.653-0.780) in the internal and external validation. Kaplan-Meier method found the 2-year LNM rate of high-risk group (35.8%) was much higher than that of the low-risk group (14.5%). The nomogram model has an advantage over the 8th AJCC TNM stage in predicting the individual 2-year LNM probability for early OSCC. CONCLUSION: Patients with low-risk nomogram score may receive neck observation; those with high-risk score should receive END.